Hello,

There's still a lot to do, even if we don't take the new programs into account.

If we're talking about chess computers, why not include chess softwares of
some historical microcomputers.
There are programs based on compiled or interpreted languages, in short BASIC, PASCAL, FORTH, C, PROLOG, LISP, and assembly languages (8080,6800,6502,Z80, 80x86, ARM and others).

But there is also the pre-microprocessor era, with first chess programs on larger systems (mainframe and then minicomputer, only physically larger if you compare... ;-) like *VAC , IBM 701 and 370 family, PDP (PDP-1 in November 1960, the first with a graphic screen) and others minicomputers.
Do not forget Supercomputer (LARC and IBM 7030 Strech,... Cray).
Here, we speak in FORTRAN, PL/1, COBOL, C and of course specific assemblers.

Expert systems created are probably the most difficult to emulate (like IA).
Massively parallel computer (the first was ILLIAC IV with 256 processors) are beyond the capabilities of a PC with MAME (perhaps a solution with distributed computers ?).

Cordialy.